Paper towel dispenser

ABSTRACT

A paper towel dispenser having a drive mechanism, comprising a bi-directional gear and a drive roller, which is activated by a lever and/or button. As the lever is depressed by a user the bi-directional gear of the drive mechanism is engaged and a length of paper towel is dispensed. When the user releases the lever, the bi-directional gear is returned to its start position by a spring. On the return stroke the spring drives the bi-directional gear and dispenses an additional length of paper towel.

FIELD

[0001] This invention relates to a dispenser for sheet material, particularly to a dispenser that dispenses individual sheets of a material, such as paper towels.

BACKGROUND

[0002] A number of dispensers exist in the prior art for dispensing paper towels and similar sheet materials, however, prior art dispensers suffer from several drawbacks.

[0003] The object of paper towel dispensers is to dispense paper towels, one sheet at a time in a way that inhibits discharging excessive paper. Prior art towel dispensers, which have mechanisms that support a roll of paper towel material, release the roll at some point during their operation. For example, a dispenser that is activated when a user pulls down on a lever will release the roll (or at least fail to lock the roll in place) when the lever is returned to its start position by a biasing element such as a spring. By holding down the lever on such dispensers such that the roll is released (or not locked) the user can draw as much towel paper out of the dispenser as is desired, resulting in wastage of paper towel. The ability to control consumption is a primary concern in the market for paper towel dispensers.

[0004] An example of one of the prior art solutions to the problem of paper wastage is to direct the paper towel through a U-shaped channel having a blade extending along the channel and having its point directed toward the bottom of the “U”. As the paper is pushed through the U-shaped channel by the drive mechanism, it follows a U-shaped path around the blade. However, if the paper is pulled through the U-shaped channel (such as when a user tries to pull the paper towel out of the dispenser) the tension in the paper forces the paper against the blade, causing it to tear. Unfortunately, paper towel varies in consistency and texture within any roll and from roll to roll and, therefore, can behave unpredictably, causing it to jam against the blade. Accordingly, there is a recognized need in the industry for paper towel dispensers that function reliably while providing for controlled consumption or, in other words, for dispensers that minimize paper wastage.

[0005] The internal mechanisms of paper towel dispensers are also prone to degradation or malfunction arising from the accumulation of paper towel fibers. In addition, the mechanisms of many prior art dispensers are difficult to access in the event of such malfunction or paper jam. Accordingly, it is an object of this invention to provide a sheet material dispenser, having a drive mechanism resistant to malfunction and/or degradation due to the accumulation of towel fibers.

[0006] The length of paper towel dispensed by the prior art paper towel dispensers is not easily adjustable, which may also contribute to paper wastage. Furthermore, when the length of the paper towel dispensed is relatively short, users will tend to activate the dispenser more quickly and/or forcefully, (i.e. by pulling down on the lever several times in rapid succession) to obtain the desired amount of towel. The risk of damage to or malfunction of the dispenser is thereby increased. In other words, it is desirable to provide a paper towel dispenser having an easily adjustable stroke length in order that paper towels with different grades and absorbencies can be used. Accordingly, it is a further object of this invention to provide a towel dispenser with an adjustable stroke length (i.e. the length of paper towel dispensed per activation can be readily varied).

[0007] It is a further object of the present invention to provide a paper towel dispenser having a simple and durable mechanism that provides for controlled paper consumption.

[0008] It is a further object of the present invention to provide a paper towel dispenser that is resistant to and easily cleared of paper jams.

SUMMARY

[0009] The invention consists of a paper towel dispenser for dispensing paper towel material. The dispenser has a drive mechanism, comprising a bi-directional gear and a drive roller, which is activated by an actuator, such as a lever or button. As the lever is depressed by a user the bi-directional gear of the drive mechanism is engaged and a length of paper towel material is dispensed. When the user releases the lever, the bi-directional gear is returned to its start position by a biasing element. On the return stroke the biasing element (e.g. a spring mechanism) drives the bi-directional gear and dispenses an additional length of paper towel. Therefore, twice as much paper towel is dispensed per user activation than in the prior art. In other words, a fewer number of strokes are necessary to dispense the necessary amount of paper towel material. This is both more convenient for users and reduces wear on the towel dispenser.

[0010] Furthermore, the drive mechanism of the present invention constantly engages the paper towel material (through the drive roller). In this manner the paper towel is locked such that, whether the lever is in the start position, partially depressed, or fully depressed, paper towel material cannot be unrolled or “stolen” from the roll in the dispenser. In other words, the paper towel is constantly engaged by the drive mechanism and therefore, consumption of the paper towel is controlled.

[0011] The stroke length of the drive mechanism, and therefore the length of paper towel material that is dispensed with each stroke of the lever, is readily adjustable.

[0012] The bi-directional gear is sealed and isolated from the interior of the dispenser such that fibers from the paper towel cannot penetrate the gear, thereby interfering with its function and necessitating maintenance and/or replacement.

[0013] The paper towel material is fed between the drive roller and an idle roller. The drive roller has high friction surface such that, as the drive roller is rotated, friction between the paper towel, idle roller and drive roller causes the paper towel to advance with the drive roller. The idle roller of the present invention is supported on a hinged or removable gate so that, when loading the paper, the idle roller is closed over the paper and drive roller rather than having to feed the paper between rollers. In addition, paper jams can be easily remedied and maintenance of the drive and idle rollers is facilitated.

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The invention itself both as to organization and method of operation, as well as additional objects and advantages thereof, will become readily apparent from the following detailed description when read in connection with the accompanying drawings wherein:

[0015]FIG. 1 is a three-quarter view of the dispenser;

[0016]FIG. 2 is a three-quarter view close up of the lower portion of the dispenser;

[0017]FIG. 3 is a three-quarter view close up of the lower portion of the dispenser with the button removed;

[0018]FIG. 4 is a cut-away view of the bi-directional gear of the dispenser;

[0019]FIG. 5 is a top view of the dispenser;

[0020]FIG. 6 shows the gate and idle roller of the dispenser;

[0021]FIG. 7 shows an alternate embodiment of the bi-directional gear having two unidirectional gears;

[0022]FIG. 8 shows an alternate embodiment of the bi-directional drive gear one traveling gear; and

[0023]FIG. 9 shows the body of the bi-directional gear of FIG. 8.

DETAILED DESCRIPTION

[0024] Referring to FIG. 1, the dispenser 10 is shown. The dispenser 10 has a body 12, which has a front side 14 and a back side 16. The back side 16 of the dispenser is normally placed against a wall when the dispenser 10 is mounted. The dispenser additionally has support arms 20 (only one of which is shown) for supporting a roll of paper towel or other sheet material. It is obvious to anyone skilled in the art that a variety of known mechanisms for supporting paper towels and/or for mounting the dispenser 10 to a support surface may be used.

[0025] The dispenser 10 has a gate 60 on the front side 14 which can be opened when loading paper towel conducting maintenance. Also shown in FIG. 1 is the lever 30, which is connected to the body 12 and outer housing 50 by pivot pin 32. The lever 30 is merely one example of a number of actuators that may be incorporated into the invention to enable the user to activate the dispenser. Other actuators, such as a dial, may be used. Button 40 extends from behind outer housing 50, which houses the inner housing 52 and the bi-directional gear of the dispenser (see FIGS. 4, 7 and 8). Protruding from the underside of the inner housing 52 is stroke length adjustment knob 70 for adjusting the length of the stroke of the bi-directional gear and, consequently, the length of paper towel material dispensed per stroke.

[0026] Referring to FIG. 2, a magnified view of the lower portion of the dispenser 10 is shown with the outer housing 50 and the lever 30 removed. Button 40 is connected by pins 42 to the bi-directional gear, (not shown) which is enclosed in inner housing 52.

[0027] Referring to FIG. 3, a magnified view similar to that of FIG. 2 is shown, this time with the button 40 removed. Pins 42 and stroke length adjustment knob 70 protrude from inner housing 52, which houses the bi-directional gear (not shown).

[0028] Referring to FIG. 4, a magnified view of the lower portion of the dispenser 10 is shown with the bi-directional gear 80 exposed. Gear 80 comprises a gear actuator 82 for engaging gears 90-95. Gear 95 is coupled to a drive roller (not shown) such that rotation of gear 95 results in rotation of the drive roller, thereby dispensing paper towel from the dispenser 10. Bi-directional gear 80 is bi-directional and, therefore, movement of gear actuator 82 in either direction (i.e. either toward the front side 14 or toward the back side 16) along slot 84 causes gear 95 to rotate in only one direction, which causes paper towel to be dispensed from the dispenser 10.

[0029] Gear actuator 82 is caused to move along slot 84 toward the back side 16 of the dispenser 10 by movement of the button 40, (see FIG. 2) which is connected to the gear actuator 82 by pins 42. Gear actuator 82 additionally has a bracket 112 at one end, to which is connected a spring 114. Spring 114 is compressed between bracket 112 and bracket 110, which is connected to the body 12 of the dispenser 10, such that gear actuator 82 is urged toward the front side 14 of the dispenser 10. It will be readily appreciated by those skilled in the art that biasing elements other than coil springs may be used in the present invention (e.g. leaf springs, elastic materials, etc.)

[0030] Gears 90 and 92 are caused to rotate by gear actuator 82 as gear actuator 82 is moved in either direction along an axis defined by slot 84. Gear actuator 82 has a toothed rack on each of its arms 86. The toothed racks are operative to engage gears 90 and 92, respectively such that they are caused to rotate as gear actuator 82 moves along slot 84.

[0031] The axes of gears 91-95 are inserted on one side into holes (not shown) in the body 12 of the dispenser 10 and on the other side into holes (not shown) in the inner housing 52 (see FIG. 2). The axes of gears 90 and 92 are inserted into holes 116, 118, each having an elongated rather than circular cross-section (the corresponding elongated holes on the other side of the gears are not shown). The shape of holes 110, 112 allows gears 90 and 92 to not only rotate about their axes but to move along lines parallel to slot 84. Gears 90 and 92 are referred to as traveling gears because they are capable of limited translation as well as rotation. As gears 90 and 92 move toward the back side 16 of the dispenser 10, gear 92 will engage gear 91 and gear 90 will become disengaged from gear 91, such that the engaged gear 92 will drive gear 91. As gears 90 and 92 move toward the front side 14 of the dispenser 10, gear 90 will engage gear 91 and gear 92 will become disengaged from gear 91, such that the engaged gear 90 will drive gear 91.

[0032] Referring to FIGS. 1, 2, 3 and 4, the dispenser 10 is activated when a user presses on an actuator in the form of lever 30, which forces the button 40 to move toward the back side 16 of the dispenser 10. Movement of the button 40 causes the gear actuator 82 to move along slot 84. Movement of the gear actuator 82 causes the toothed rack (not shown) on arm 86 to force gear 92 toward the back side 16 of the dispenser such that it engages gear 91, and causes the toothed rack (not shown) on arm 88 to force gear 90 toward the back side 16 such that it disengages from gear 91. Movement of the gear actuator 82 also causes gear 92 to rotate and, therefore, to drive gear 91. In other words, movement of the gear actuator 82 toward the back side 16 drives gears 92, 91, 93, 94 and 95 of bi-directional gear 80. Movement of gear 95 causes paper towel to be dispensed by the drive roller (not shown).

[0033] As the user then releases the lever 30, gear actuator 82 is moved toward the front side 14 of the dispenser 10 by spring 114. Movement of gear actuator 82 toward the front side 14 causes the toothed racks (not shown) on arms 86, 88 to force both of gears 90 and 92 to move toward the front side 14 and to rotate. Gear 90 thereby engages and drives gear 91, and gear 92 thereby becomes disengaged from gear 91. Movement of gear actuator 82 toward the front side 14 thereby drives gears 90, 91, 93, 94 and 95 of bi-directional gear 80. Movement of gear 95 again causes paper towel to be dispensed by the drive roller. Regardless of the direction of movement of the gear actuator 82, the drive roller is rotated in the same direction.

[0034] Referring to FIG. 4, the movement of the gear actuator 82, and the amount of paper towel material dispensed, can be limited by the stroke length adjustment knob 70. As the knob 70 is rotated about its axis the screw-threaded portion 72 forces the block 74 upwards. Block 74 has a stepped face that is operative to engage the stepped face portion of the gear actuator 82, thereby limiting its movement.

[0035]FIG. 5 is a top view of the dispenser 10. Drive roller 98 extends across the interior of the dispenser 10 and is supported at each end where it contacts the walls of the dispenser 10. One end 100 of the drive roller 98 is coupled to the drive gear 95 of the bi-directional gear (see FIG. 4). Drive roller 98 contacts idle roller 62, which is supported on the gate 60 of the dispenser 10. The paper towel (not shown), which is supported on support arms 20, (only one support arm is shown) is fed between drive roller 98 and idle roller 62. Rotation of the drive gear 95 causes rotation of the drive roller 98, and the paper towel is caused to advance by friction on the paper towel between the drive roller 98 and idle roller 62.

[0036]FIG. 6 shows the idle roller 62 mounted on the gate 20. Referring to FIGS. 1, 5 and 6, the gate 20 can be removed, or opened if mounted on a hinge to allow access to the idle roller 62 and drive roller 98.

[0037]FIG. 7 shows an alternate embodiment of the bi-directional gear 117 having two unidirectional gears 120 and 122 and no traveling gears. Each of the unidirectional gears 120 and 122 is comprised of an inner component 134 and 136, respectively, each comprising a toothed wheel and a three-armed element, and an outer component 130 and 132, respectively. When rotated in the clockwise direction, the inner component 136 engages the outer component 132 so as to cause it to rotate. When rotated in the counter clockwise direction the three-armed element of the inner component 136 merely slips within the outer component 132 such that the outer component 132 remains stationary. The unidirectional gear 122 is complementary to the other gear 120 such that rotation of the gear 122 in the clockwise direction causes the inner component 134 to slip against the outer component 130. Rotation of the gear 122 in the counterclockwise sense causes the inner component 134 to engage the outer component 130 so as to cause it to rotate. The unidirectional gears 120, 122 are coupled to the drive roller (not shown) such that rotation of either one causes the drive roller to advance the paper towel. The unidirectional gears 120, 122 are rotated by movement of the toothed rack of gear actuator 124, which is connected to the button 40 of FIGS. 1 and 2, such that pressure exerted by a user on the lever 30 activates the bi-directional gear 117. A biasing mechanism (not shown) moves the gear actuator 124 back to its original position, again driving the gear 117 and advancing the paper towel.

[0038]FIG. 8 shows an alternate embodiment of the bi-directional gear 148 having one traveling gear 150. Traveling gear 150 is capable of limited lateral movement such that it is capable of engaging either one of gears 152 and 154. Rotation of gears 152 or 154 will cause gear 156 and drive gear 158 to rotate. Drive gear 158 is coupled to the drive roller (not shown) and, therefore, will advance the paper towel from the dispenser. Gear actuator 160 has a toothed rack, which engages traveling gear 150. Movement of the gear actuator 160 causes the traveling gear 150 to move laterally (so as to engage one of gears 152 and 154) and to rotate. Referring to FIGS. 1, 2, and 8, gear actuator 160 is coupled to the button 40 such that when a user depresses the lever 30 the paper towel is dispensed. As with the previously discussed gears, a biasing mechanism (not shown) returns the lever 30, button 40 and bi-directional gear 148 to the start position, advancing the paper towel in the process.

[0039]FIG. 9 shows the body 162 and gear actuator 160 of the bi-directional gear 148 of FIG. 8. Referring to FIGS. 8 and 9, the body 162 has holes 164-172 which receive the axles of gears 150-158. Hole 166 has an elongated shape in order to allow traveling gear 150 to move laterally.

[0040] Referring to FIGS. 1-4, 7 and 8, the bi-directional gear 80, 117, 148 is sealed and isolated from the interior of the dispenser such that fibers from the paper towel cannot penetrate the gear 80, 117, 148, thereby interfering with its function and necessitating maintenance and/or replacement. The invention additionally contemplates an embodiment wherein the bi-directional gear 80, 117, 148 is in the form of a cassette that may be incorporated into any of a number of paper towel dispenser designs. The cassette form of the bi-directional gear 80, 117, 148 provides cost and space savings with respect to shipping because the cassettes are much smaller than the paper towel dispensers. In addition, the cassettes enable purchasers greater flexibility in designing and/or sourcing dispensers.

[0041] Referring again to FIG. 8, the bi-directional gear 148 has been found, in some instances, to bind and/or jam. More specifically, the traveling gear 150 may, under abnormal conditions, bind on gears 154 and 152. It has been found that such binding is effectively prevented if the size of the traveling gear 150 is increased relative to gears 154 and 152. Variation of the sizes of the gears in other embodiments of the bi-directional gears, including gears 80, 117 of FIGS. 4 and 7 as well as embodiments not shown herein (but which would be a simple matter of design choice for anyone having ordinary skill in the art) provides a simple way to optimize operation such that the bi-directional gears are resistant to binding and/or jamming.

[0042] Referring again to FIG. 8, jamming and/or binding of the traveling gear 150 is further reduced if gears 154 and 152 are capable of a slight translational movement in a direction perpendicular to the lateral translation of the traveling gear 150. In this manner, when engaged by the traveling gear 150, the gears 152 and 154 will be slightly vertically displaced with respect to one another so that the risk of binding on the traveling gear 150 is reduced but without affecting the ability to engage the traveling gear 150.

[0043] Accordingly, while this invention has been described with reference to illustrative embodiments, this description is not intended to be construed in a limiting sense. Various modifications of the illustrative embodiments, as well as other embodiments of the invention, will be apparent to persons skilled in the art upon reference to this description. It is therefore contemplated that the appended claims will cover any such modifications or embodiments as fall within the scope of the invention. 

We claim:
 1. A paper towel dispenser comprising a drive roller, a user operated actuator, and a bi-directional gear, said bi-directional gear coupled to said drive roller and to said user operated actuator and operative to rotate said drive roller in a single direction of rotation to discharge said paper towel material, wherein one full cycle of said bi-directional gear is made up of a 1^(st) stroke and a return stroke, both said 1^(st) stroke and said return stroke operative to rotate said drive roller in said single direction, said 1^(st) stroke being driven by a force exerted by a user on said actuator and said return stroke being driven by a biasing element.
 2. A paper towel dispenser according to claim 1, wherein said drive roller is constantly engaged with said paper towel throughout said cycle of said bi-directional gear such that consumption of said paper towel is controlled.
 3. A paper towel dispenser according to claim 1, wherein said bi-directional gear comprises two unidirectional gears.
 4. A paper towel dispenser according to claim 1, wherein said bi-directional gear comprises one traveling gear.
 5. A paper towel dispenser according to claim 1, wherein said bi-directional gear comprises two traveling gears.
 6. A paper towel dispenser according to claim 1, wherein said bi-directional gear is sealed such that fibers from said paper towel cannot penetrate said bi-directional gear.
 7. A paper towel dispenser according to claim 1, wherein said roll of paper towel is supported on said drive roller.
 8. A paper towel dispenser according to claim 1, wherein said user operated actuator comprises a lever for transferring said force exerted by said user to said bi-directional gear.
 9. A paper towel dispenser according to claim 1, further comprising stroke-length adjustment means operative to limit lengths of said 1^(st) and return strokes.
 10. A paper towel dispenser according to claim 1, wherein said biasing mechanism comprises a coil spring.
 11. A paper towel dispenser according to claim 1, further comprising an idle roller in contact with said drive roller.
 12. A paper towel dispenser according to claim 1, wherein said bi-directional gear is in the form of a cassette, which is inserted into the paper towel dispenser.
 13. A paper towel dispenser according to claim 1, wherein said bi-directional gear includes gears of unequal sizes.
 14. A drive mechanism for a paper towel dispenser having a drive roller and a user operated actuator, said drive mechanism comprising a bi-directional gear couplable to said drive roller and to said user operated actuator and operative, when so coupled, to rotate said drive roller in a single direction of rotation to discharge paper towel material, wherein one full cycle of said bi-directional gear is made up of a 1^(st) stroke and a return stroke, both said 1^(st) stroke and said return stroke operative to rotate said drive roller in said single direction, said 1^(st) stroke being driven by a force exerted by a user on said actuator and said return stroke being driven by a biasing element.
 15. A paper towel dispenser according to claim 14, wherein said drive roller is constantly engaged with said paper towel throughout said cycle of said bi-directional gear such that consumption of said paper towel is controlled.
 16. A paper towel dispenser according to claim 14, wherein said bi-directional gear comprises two unidirectional gears.
 17. A paper towel dispenser according to claim 14, wherein said bi-directional gear comprises one traveling gear.
 18. A paper towel dispenser according to claim 14, wherein said bi-directional gear comprises two traveling gears.
 19. A paper towel dispenser according to claim 14, wherein said bi-directional gear is sealed such that fibers from said paper towel cannot penetrate said bi-directional gear.
 20. A paper towel dispenser according to claim 14, wherein said roll of paper towel is supported on said drive roller.
 21. A paper towel dispenser according to claim 14, wherein said user operated actuator comprises a lever for transferring said force exerted by said user to said bi-directional gear.
 22. A paper towel dispenser according to claim 14, further comprising stroke-length adjustment means operative to limit lengths of said 1^(st) and return strokes.
 23. A paper towel dispenser according to claim 14, wherein said biasing mechanism comprises a coil spring.
 24. A paper towel dispenser according to claim 14, further comprising an idle roller in contact with said drive roller.
 25. A paper towel dispenser according to claim 14, wherein said bi-directional gear is in the form of a cassette, which is inserted into the paper towel dispenser.
 26. A paper towel dispenser according to claim 14, wherein said bi-directional gear includes gears of unequal sizes. 